4. Temper: Whisk a little of the coffee mixture into yolks. Whisk yolks back into coffee mixture, and cook over medium heat until thick enough to coat the back of a spoon, about 3 minutes. Stir in coffee liqueur and vanilla. Strain this custard through a fine-mesh sieve into a large glass measuring cup. (Makes about 1 cup coffee custard.)

5. Serve: Pour 3 to 4 tablespoons hot coffee custard over each serving of ice cream. Top with a spoonful of whipped cream. Enjoy.